package com.luom.springbootinit.service.impl;

import java.util.*;

import cn.hutool.core.bean.BeanUtil;
import cn.hutool.core.bean.copier.CopyOptions;
import cn.hutool.core.collection.CollUtil;
import cn.hutool.core.util.ObjectUtil;
import cn.hutool.core.util.RandomUtil;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.luom.springbootinit.common.ErrorCode;
import com.luom.springbootinit.constant.CommonConstant;
import com.luom.springbootinit.constant.RedisConstant;
import com.luom.springbootinit.exception.BusinessException;
import com.luom.springbootinit.mapper.UserMapper;
import com.luom.springbootinit.model.dto.borrowRecord.BorrowRecordQueryRequest;
import com.luom.springbootinit.model.dto.user.UserQueryRequest;
import com.luom.springbootinit.model.dto.user.UserResetPasswordRequest;
import com.luom.springbootinit.model.entity.User;
import com.luom.springbootinit.model.enums.UserRoleEnum;
import com.luom.springbootinit.model.vo.LoginUserVO;
import com.luom.springbootinit.model.vo.UserAnalysisVO;
import com.luom.springbootinit.model.vo.UserVO;
import com.luom.springbootinit.service.UserService;
import com.luom.springbootinit.utils.RegexUtils;
import com.luom.springbootinit.utils.SendEmail;
import com.luom.springbootinit.utils.SqlUtils;
import io.lettuce.core.RedisCommandExecutionException;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.BeanUtils;
import org.springframework.dao.DataAccessException;
import org.springframework.data.redis.RedisConnectionFailureException;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;
import org.springframework.util.DigestUtils;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import java.util.concurrent.TimeUnit;
import java.util.stream.Collectors;

import static com.luom.springbootinit.constant.UserConstant.USER_LOGIN_STATE;

/**
 * 用户服务实现
 */
@Service
@Slf4j
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements UserService {

    /**
     * 盐值，混淆密码
     */
    public static final String SALT = "luom";

    @Resource
    private SendEmail sendEmail;

    @Resource
    private StringRedisTemplate stringRedisTemplate;

    @Resource
    private UserMapper userMapper;

    @Override
    public int userRegister(String userAccount, String userPassword, String checkPassword) {
        // 1. 校验
        if (StringUtils.isAnyBlank(userAccount, userPassword, checkPassword)) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "参数为空");
        }
        if (userAccount.length() < 4) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "用户账号过短");
        }
        if (userPassword.length() < 8 || checkPassword.length() < 8) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "用户密码过短");
        }
        // 密码和校验密码相同
        if (!userPassword.equals(checkPassword)) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "两次输入的密码不一致");
        }
        synchronized (userAccount.intern()) {
            // 账户不能重复
            QueryWrapper<User> queryWrapper = new QueryWrapper<>();
            queryWrapper.eq("userAccount", userAccount);
            long count = this.baseMapper.selectCount(queryWrapper);
            if (count > 0) {
                throw new BusinessException(ErrorCode.PARAMS_ERROR, "账号重复");
            }
            // 2. 加密
            String encryptPassword = DigestUtils.md5DigestAsHex((SALT + userPassword).getBytes());
            // 3. 插入数据
            User user = new User();
            user.setUserAccount(userAccount);
            user.setUserPassword(encryptPassword);
            user.setUserName("user_" + RandomUtil.randomString(6));
            boolean saveResult = this.save(user);
            if (!saveResult) {
                throw new BusinessException(ErrorCode.SYSTEM_ERROR, "注册失败，数据库错误");
            }
            return user.getId();
        }
    }

    @Override
    public LoginUserVO userLogin(String userAccount, String userPassword, HttpServletRequest request) {
        // 1. 校验
        if (StringUtils.isAnyBlank(userAccount, userPassword)) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "参数为空");
        }
        if (userAccount.length() < 4) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "账号错误");
        }
        if (userPassword.length() < 8) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "密码错误");
        }
        // 2. 加密
        String encryptPassword = DigestUtils.md5DigestAsHex((SALT + userPassword).getBytes());
        // 查询用户是否存在
        QueryWrapper<User> queryWrapper = new QueryWrapper<>();
        queryWrapper.eq("userAccount", userAccount);
        queryWrapper.eq("userPassword", encryptPassword);
        User user = this.baseMapper.selectOne(queryWrapper);
        // 用户不存在
        if (user == null) {
            log.info("user login failed, userAccount cannot match userPassword");
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "用户不存在或密码错误");
        }
        // 检查是否禁用
        if (UserRoleEnum.BAN.getValue().equals(user.getUserRole())) {
            throw new BusinessException(ErrorCode.NO_AUTH_ERROR, "该用户已被封禁");
        }

        // 3. 记录用户的登录态
        request.getSession().setAttribute(USER_LOGIN_STATE, user);
        // 4.写入缓存
        saveUser2Redis(user);
        return this.getLoginUserVO(user);
    }


    /**
     * 获取当前登录用户
     *
     * @param request
     * @return
     */
    @Override
    public User getLoginUser(HttpServletRequest request) {
        // 先判断是否已登录
        Object userObj = request.getSession().getAttribute(USER_LOGIN_STATE);
        User currentUser = (User) userObj;
        if (currentUser == null || currentUser.getId() == null) {
            throw new BusinessException(ErrorCode.NOT_LOGIN_ERROR);
        }
        // 查询用户信息
        int userId = currentUser.getId();
        // 从redis中根据id查询
        Map<Object, Object> map = stringRedisTemplate.opsForHash().entries(RedisConstant.LOGIN_USER_KEY + userId);

        if (!map.isEmpty()) {
            currentUser = BeanUtil.toBean(map, User.class);
        } else {
            // 从数据库中查询
            currentUser = getById(userId);
            if (currentUser != null) {
                saveUser2Redis(currentUser);
            }
        }

        return currentUser;
    }

    // 将用户信息写入redis
    private void saveUser2Redis(User currentUser) {
        Map<String, Object> userMap = BeanUtil.beanToMap(currentUser, new HashMap<>(),
                CopyOptions.create()
                        .setIgnoreNullValue(true)
                        .setFieldValueEditor((fieldName, fieldValue) -> {
                            if (fieldValue == null) {
                                return "";
                            }
                            return fieldValue.toString();
                        }));
        try {
            stringRedisTemplate.opsForHash().putAll(RedisConstant.LOGIN_USER_KEY + currentUser.getId(), userMap);
            stringRedisTemplate.expire(RedisConstant.LOGIN_USER_KEY + currentUser.getId(), 60, TimeUnit.MINUTES);
        }catch (RedisConnectionFailureException e) {
            // 捕获与Redis连接相关的失败
            System.err.println("Redis连接失败: " + e.getMessage());
            log.info("Redis连接失败: {}", e.getMessage());
        } catch (RedisCommandExecutionException e) {
            // 捕获Redis命令执行时的失败（例如，语法错误、操作不支持等）
            System.err.println("Redis命令执行失败: " + e.getMessage());
            log.info("Redis命令执行失败: {}", e.getMessage());
        }
    }

    /**
     * 获取当前登录用户（允许未登录）
     *
     * @param request
     * @return
     */
    @Override
    public User getLoginUserPermitNull(HttpServletRequest request) {
        // 先判断是否已登录
        Object userObj = request.getSession().getAttribute(USER_LOGIN_STATE);
        User currentUser = (User) userObj;
        if (currentUser == null || currentUser.getId() == null) {
            return null;
        }
        // 从数据库查询（追求性能的话可以注释，直接走缓存）
        int userId = currentUser.getId();
        return this.getById(userId);
    }

    /**
     * 是否为管理员
     *
     * @param request
     * @return
     */
    @Override
    public boolean isAdmin(HttpServletRequest request) {
        // 仅管理员可查询
        Object userObj = request.getSession().getAttribute(USER_LOGIN_STATE);
        User user = (User) userObj;
        return isAdmin(user);
    }

    @Override
    public boolean isAdmin(User user) {
        return user != null && UserRoleEnum.ADMIN.getValue().equals(user.getUserRole());
    }

    /**
     * 用户注销
     *
     * @param request
     */
    @Override
    public boolean userLogout(HttpServletRequest request) {
        if (request.getSession().getAttribute(USER_LOGIN_STATE) == null) {
            throw new BusinessException(ErrorCode.OPERATION_ERROR, "未登录");
        }
        // 移除登录态
        User user = (User) request.getSession().getAttribute(USER_LOGIN_STATE);
        request.getSession().removeAttribute(USER_LOGIN_STATE);
        stringRedisTemplate.delete(RedisConstant.LOGIN_USER_KEY + user.getId());
        return true;
    }

    @Override
    public LoginUserVO getLoginUserVO(User user) {
        if (user == null) {
            return null;
        }
        LoginUserVO loginUserVO = new LoginUserVO();
        BeanUtils.copyProperties(user, loginUserVO);
        return loginUserVO;
    }

    @Override
    public UserVO getUserVO(User user) {
        if (user == null) {
            return null;
        }
        UserVO userVO = new UserVO();
        BeanUtils.copyProperties(user, userVO);
        return userVO;
    }

    @Override
    public List<UserVO> getUserVO(List<User> userList) {
        if (CollUtil.isEmpty(userList)) {
            return new ArrayList<>();
        }
        return userList.stream().map(this::getUserVO).collect(Collectors.toList());
    }

    @Override
    public QueryWrapper<User> getQueryWrapper(UserQueryRequest userQueryRequest) {
        if (userQueryRequest == null) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "请求参数为空");
        }
        Integer id = userQueryRequest.getId();
        String userName = userQueryRequest.getUserName();
        String userRole = userQueryRequest.getUserRole();
        String userAccount = userQueryRequest.getUserAccount();
        String email = userQueryRequest.getEmail();
        String phone = userQueryRequest.getPhone();
        String sortField = userQueryRequest.getSortField();
        String sortOrder = userQueryRequest.getSortOrder();
        QueryWrapper<User> queryWrapper = new QueryWrapper<>();
        queryWrapper.eq(id != null, "id", id);
        queryWrapper.eq(StringUtils.isNotBlank(userRole), "userRole", userRole);
        queryWrapper.like(StringUtils.isNotBlank(userName), "userName", userName);
        queryWrapper.like(StringUtils.isNotBlank(userAccount), "userAccount", userAccount);
        queryWrapper.like(StringUtils.isNotBlank(email), "email", email);
        queryWrapper.like(StringUtils.isNotBlank(phone), "phone", phone);
        queryWrapper.orderBy(SqlUtils.validSortField(sortField), sortOrder.equals(CommonConstant.SORT_ORDER_ASC),
                sortField);
        return queryWrapper;
    }

    @Override
    public LoginUserVO userLoginByEmail(String userEmail, String code, HttpServletRequest request) {
        // 1. 校验
        if (StringUtils.isAnyBlank(userEmail, code)) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "参数为空");
        }
        if (RegexUtils.isEmailInvalid(userEmail)) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "邮箱错误");
        }
        // 2. 加密
//        String encryptPassword = DigestUtils.md5DigestAsHex((SALT + code).getBytes());

        //3.从redis中获取验证码并校验
        String cacheCode = stringRedisTemplate.opsForValue().get(RedisConstant.LOGIN_CODE_KEY + userEmail);
        if (cacheCode == null || !cacheCode.equals(code)) {
            //4.不一致，返回错误信息
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "验证码错误");
        }

        //5.一致，根据邮箱查询用户
        User user = query().eq("email", userEmail).one();

        //6.不存在，创建新用户并保存
        if (user == null) {
            user = createWithEmail(userEmail);
        }
        // 检查是否禁用
        if (UserRoleEnum.BAN.getValue().equals(user.getUserRole())) {
            throw new BusinessException(ErrorCode.NO_AUTH_ERROR, "该用户已被封禁");
        }
        // 7. 记录用户的登录态
        request.getSession().setAttribute(USER_LOGIN_STATE, user);
        return this.getLoginUserVO(user);
    }

    @Override
    public Boolean getCodeByEmail(String email) {
        // 1. 校验
        if (StringUtils.isAnyBlank(email)) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "参数为空");
        }
        if (RegexUtils.isEmailInvalid(email)) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "邮箱错误");
        }
        //生成验证码
        String code = RandomUtil.randomNumbers(6);
        //发送邮箱
        sendEmail.sendMail(email, code);
        //保存验证码到redis,key: email,value:code,过期时间3分钟
        stringRedisTemplate.opsForValue().set(RedisConstant.LOGIN_CODE_KEY + email, code, 3L, TimeUnit.MINUTES);
        return true;
    }

    @Override
    public boolean updatePassword(UserResetPasswordRequest userResetPasswordRequest, HttpServletRequest request) {
        String email = userResetPasswordRequest.getEmail();
        String code = userResetPasswordRequest.getCode();
        String userPassword = userResetPasswordRequest.getUserPassword();
        String checkPassword = userResetPasswordRequest.getCheckPassword();

        // 密码和校验密码相同
        if (!userPassword.equals(checkPassword)) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "两次输入的密码不一致");
        }
        String redisCode = stringRedisTemplate.opsForValue().get(RedisConstant.LOGIN_CODE_KEY + email);
        if (redisCode == null || !redisCode.equals(code)) {
            //不一致，返回错误信息
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "验证码错误");
        }
        // 判断是否是自己
        if (!email.equals(getLoginUser(request).getEmail())) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "只能修改自己的密码");
        }
        //修改密码
        boolean update = update().set("userPassword", DigestUtils.md5DigestAsHex((SALT + userPassword).getBytes())).eq("email", email).update();

        return update;
    }

    /**
     * 获取用户借阅量前五
     * @return
     */
    @Override
    public List<UserAnalysisVO> getTop5User() {
        return userMapper.getTop5User();
    }

    private User createWithEmail(String userEmail) {
        User user = new User();
        user.setEmail(userEmail);
        user.setUserName("user_" + RandomUtil.randomString(6));
        user.setUserAccount(userEmail);
        user.setUserPassword(DigestUtils.md5DigestAsHex((SALT + "12345678").getBytes()));
        save(user);
        return user;
    }
}
